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Detecting 1/10th scaled structures in dielectric media using monostatic X-band radar scattering measurements

John D. Kekis, Markus E. Testorf, Michael A. Fiddy, Robert H. Giles, Michael A. Fiddy, Rick P. Millane
2000 Image Reconstruction from Incomplete Data  
in various types of soil using a l-GHz ground penetrating radar by establishing a 1/10th-scale laboratory environment with two spot-focussing X-band (10-GHz) lens antennae and an HP85 lOB Network Analyzer  ...  The monostatic X-band measurements were acquired in an anechoic environment, and digital images of the backscattered radar data from the 1/10th-scale composite scenes were processed using inverse synthetic  ...  Robert Giles, for their support ofthis research. This project was funded by the National Ground Intelligence Center.  ... 
doi:10.1117/12.409277 fatcat:i2hlcxuwwbdixbs4lfwovmgnla

Overview of the D3R Observations during the IFloodS Field Experiment with Emphasis on Rainfall Mapping and Microphysics

Robert M. Beauchamp, V. Chandrasekar, Haonan Chen, Manuel Vega
2015 Journal of Hydrometeorology  
An overview of the D3R's calibration and observations is presented. A method for attenuation correction of Ka-band observations using Ku-band results is introduced.  ...  Dual-frequency ratio estimates in stratiform rain and ice are presented and compared with theoretical values.  ...  The authors acknowledge the support of the GPM program, David Wolff and David Marks for NPOL support, and Mathew Schwaller and Walter Petersen for deployment and logistics support.  ... 
doi:10.1175/jhm-d-15-0023.1 fatcat:qmntpgrvxnfmhfs4jogds5y3ba

Analysis of a Dynamic Calibration Target for Through-Wall and Through-Rubble Motion Sensing Doppler Radar

Ram M. Narayanan, Michael J. Harner, John R. Jendzurski, Nicholas G. Paulter
2021 Instruments  
The aspect-independence of a sphere allows for more accurate and repeatable calibration of a radar than using a nonspherical calibration artifact.  ...  For Doppler radar testing, it is desired to apply these calibration advantages to a dynamically expanding-and-contracting sphere-like device that can emulate motions of the human body.  ...  Calibration Sphere for Mimicking Human Radar Cross Section Calibration The PEC Sphere  ... 
doi:10.3390/instruments5040037 fatcat:sjtzq6jitfflxcdtjzstdtm5b4

Radar/rain-gauge comparisons on squall lines in Niamey, Niger for the AMMA

B. Russell, E.R. Williams, M. Gosset, F. Cazenave, L. Descroix, N. Guy, T. Lebel, A. Ali, F. Metayer, G. Quantin
2010 Quarterly Journal of the Royal Meteorological Society  
(The sphere calibration and the Tropical Rainfall Measuring Mission TRMM -radar calibration are inconsistent at the 1-2 dB level for unknown reasons.)  ...  Massachusetts Institute of Technology C-band radar observations are integrated with rainfall measurements from an extensive network of gauges in Niamey, Niger, West Africa, for the African Monsoon and  ...  Discussions of a more general nature on radar/gauge comparisons with D. Atlas, P.Austin, S.Geotis (deceased),  ... 
doi:10.1002/qj.548 fatcat:4mia3bnkp5fizmirlf6qpwmeci

High-precision RCS measurement of aircraft's weak scattering source

Chufeng Hu, Nanjing Li, Weijun Chen, Linxi Zhang
2016 Chinese Journal of Aeronautics  
Secondly, we carried out the spectral transform of the reflectivity distribution and eventually obtained the RCS of the weak scattering source through calibration.  ...  This paper proposes separating and extracting the two-dimensional (2D) reflectivity distribution of the weak scattering source with the microwave imaging algorithm and spectral transform so as to enhance  ...  Acknowledgements This study was co-supported by the National Natural Science Foundation of China (Nos. 61201320, 61371023) and the Fundamental Research Funds for the Central Universities of China (No.  ... 
doi:10.1016/j.cja.2016.03.003 fatcat:q43xmgjij5cypcpq7lm2cedeiq

Low-Cost CW-LFM Radar Sensor at 100 GHz

Beatriz Mencia-Oliva, Jesús Grajal, Omar A. Yeste-Ojeda, Gorka Rubio-Cidre, Alejandro Badolato
2013 IEEE transactions on microwave theory and techniques  
This paper presents a V^-band high-resolution radar sensor for short-range applications.  ...  Low-cost technologies have been properly selected in order to implement a versatile and easily scalable radar system.  ...  The measurement of a target with known radar cross section (RCS), such as a metallic sphere, is suitable for measuring the PSF.  ... 
doi:10.1109/tmtt.2012.2235457 fatcat:3fjyj2pftnhpnpajyhis5ld7vi

3D imaging by fast deconvolution algorithm in short-range UWB radar for concealed weapon detection

Timofey Savelyev, Alexander Yarovoy
2013 International journal of microwave and wireless technologies  
(ultra-wideband) radar with synthetic or real-array aperture is proposed.  ...  3D imaging by fast deconvolution algorithm in short-range UWB radar for concealed weapon detection timofey savelyev 1,2 and alexander yarovoy 1 A fast imaging algorithm for real-time use in short-range  ...  Figure 2 illustrates the efficiency of deconvolution for signals acquired from a small metal sphere and a metal gun, more specifically 1% error and 35% instability.  ... 
doi:10.1017/s1759078713000251 fatcat:yuzda2ervjd7fh6epy6q26bdvi

Real-time through-wall imaging using an ultrawideband multiple-input multiple-output (MIMO) phased array radar system

T S Ralston, G L Charvat, J E Peabody
2010 2010 IEEE International Symposium on Phased Array Systems and Technology  
A real-time acquisition and processing architecture has been developed for an ultrawideband (UWB) S-band (2-4 GHz) multiple-input multiple-output (MIMO) phased array radar system that facilitates greater  ...  Experiments successfully image low radar cross section (RCS) objects, fast moving objects in free-space, and a human behind a 10 cm-thick solid concrete wall.  ...  All antenna switches (SW1-4) are solid state and digitally controlled by the PC.  ... 
doi:10.1109/array.2010.5613314 fatcat:eozvpqzj2vfb3dif42ncdnpfsu

Multifrequency radar observations of clouds and precipitation including the G-band

Katia Lamer, Mariko Oue, Alessandro Battaglia, Richard J. Roy, Ken B. Cooper, Ranvir Dhillon, Pavlos Kollias
2021 Atmospheric Measurement Techniques  
The field experiment, which coordinated an X-, Ka-, W- and G-band radar, revealed that the Ka–G pairing can generate differential reflectivity signal several decibels larger than the traditional Ka–W pairing  ...  Observed peculiar radar reflectivity patterns also suggest that G-band radars could be used to gain insight into the melting behavior of small ice crystals.  ...  Zeen Zhu, Samantha Nebylitsa, Jacob Segall and Kristofer Tuftedal for launching radiosondes from the SBRO.  ... 
doi:10.5194/amt-14-3615-2021 fatcat:54vw5ofisjbglapegfazcsn5tm

Experiment of Azimuth-invariant Bistatic UHF UWB SAR

Hongtu Xie, Shaoying Shi, Junfa Mao, Fuhai Li, Daoxiang An, Zhimin Zhou, Guoqian Wang
2018 Journal of Physics, Conference Series  
Bistatic ultrahigh frequency ultrawideband synthetic aperture radar (UHF UWB SAR) has the well ability of the penetrating the foliage, high-resolution imaging and providing the increased information.  ...  Bistatic image was obtained using the subaperture spectrumequilibrium method integrated with the fast factorized back projection algorithm (FFBPA).  ...  Finally, we find that only a metallic sphere in the white circle is seen.  ... 
doi:10.1088/1742-6596/960/1/012037 fatcat:sve5www34zcfjl3ceecrguujge

MEASURED COMPLEX PERMITTIVITY OF WALLS WITH DIFFERENT HYDRATION LEVELS AND THE EFFECT ON POWER ESTIMATION OF TWRI TARGET RETURNS

Christopher Thajudeen, Ahmad Hoorfar, Fauzia Ahmad, Traian Dogaru
2011 Progress in Electromagnetics Research B  
A modified radar range equation, which analytically accounts for the wall effects, including multiple reflections within a given homogeneous or layered wall, is then employed in conjunction with wideband  ...  The results for various wall types, including drywall, brick, solid concrete, and cinder block, the latter two under both wet and dry conditions, are presented.  ...  Approved for public release. Distribution unlimited.  ... 
doi:10.2528/pierb10091004 fatcat:cfrwxctkhnb23hypooxnk7etfu

EFFECTS OF INFLATED CONE ON SATELLITE'S RADAR CROSS SECTIONS IN S-BAND VIA FDTD SIMULATIONS

Shen Shou Max Chung
2015 Progress In Electromagnetics Research M  
The best strategy for satellite self-defense is orbit change.  ...  In this study we examine the accuracy of a commercial FDTD code with a theoretical Mie scattering RCS, and use it to calculate the RCS of this so-called stealth satellite in the S-band, and analyze its  ...  together with the Dorchia Communications Company, Taiwan, for providing a provisional license and technical assistance for the GEMS simulation software.  ... 
doi:10.2528/pierm15033102 fatcat:fii4s74ykbeedl46r4bdsqa6ry

Improvement in SNR by Adaptive Range Gates for RCS Measurements in the THz Region

Pang, Zeng, Yang, Deng, Wang, Qin
2019 Electronics  
However, this method may not work to expectations, especially for targets with a large length-width ratio. This is because the effective target zone is dependent on the aspect angle.  ...  One of the major concerns in radar cross-section (RCS) measurements is the isolation of the target echo from unwanted spurious signals.  ...  (THz-TDS)-based systems and solid-state THz systems [7] [8] [9] [10] .  ... 
doi:10.3390/electronics8070805 fatcat:cfvtuqkgrvdf5n3mxxzuka37fa

Asteroid 16 Psyche: Shape, Features, and Global Map

Michael K. Shepard, Katherine de Kleer, Saverio Cambioni, Patrick A. Taylor, Anne K. Virkki, Edgard G. Rívera-Valentin, Carolina Rodriguez Sanchez-Vahamonde, Luisa Fernanda Zambrano-Marin, Christopher Magri, David Dunham, John Moore, Maria Camarca
2021 The Planetary Science Journal  
Using 30 calibrated radar echoes, we find Psyche's overall radar albedo to be 0.34 +/- 0.08 suggesting that the upper meter of regolith has a significant metal (i.e., Fe-Ni) content.  ...  or CH/CB chondrites and peppered with localized regions of high metal concentrations.  ...  ALMA is a partnership of ESO (representing its member states), NSF (USA), and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic  ... 
doi:10.3847/psj/abfdba fatcat:v4elvtkxzbeddctnskp4lmmb4q

Scattering characteristics of high-resolution meteor head echoes detected at multiple frequencies

S. Close
2002 Journal of Geophysical Research  
density sufficiently high that its plasma frequency exceeds the radar frequency (overdense reflection).  ...  The primary sensor was the ARPA Long-Range Tracking and Instrumentation Radar (ALTAIR) radar operating at 160 MHz with 30 m range resolution and 422 MHz with 7.5 m range resolution, including both interferometric  ...  This RCS value substantially exceeds the minimum detectable RCS of the S-band system and, if this were a metal target, the radar would have detected a signal.  ... 
doi:10.1029/2002ja009253 fatcat:wut2hiqadvh3hepvlugdgk5rzi
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